// JavaScript Document
function LimmitDrag(id)
{
	 Drag.call(this,id);    //继承属性
}


for(var i in Drag.prototype)
{
		LimmitDrag.prototype[i] = Drag.prototype[i];
}


LimmitDrag.prototype.Move = function (ev)
{
		var oEvent = ev || event;
		var X = oEvent.clientX-this.disX;
		var Y = oEvent.clientY-this.disY;
	
	if(X < 0)
	{
				X=0
	}
	else if(X>document.documentElement.clientWidth - this.oDiv.offsetWidth)
	{
				X =document.documentElement.clientWidth - this.oDiv.offsetWidth;
	}
		this.oDiv.style.left = X + 'px';
		this.oDiv.style.top = Y + 'px';
}